Adjustable light beam director having removable verticle baffles



N0v.24,.197o W,M E|KENBERRY ETAL 3,543,235

ADJUSTABLE LIGHT BEAM DIRECTOR HAVING REMOVABLE VERTICAL BAFFLES FiledMay 19, 1969 I 2 sheets-sheet 1 FIG! B 2 fA Www/W50? ATTORNEYS.

NOV. 24, 1970 w, M ElKENBERRY ETAL 3,543,235

l ADJUSTABLE LIGHT BEAM DIRECTOR HAVING REMOVABLEVERTICAL BAFFLES Filedmay 19, 1969 433' /4" sPAclNG X/SZ L/ INVENTORS.

KEN BERRY HUPPERT 52 |45" sPAclNG le f' 1.". \L\ 2 3A 7o l2 UnitedStatesPatent O U.S. Cl. 340-107 11 Claims ABSTRACT OF THE DISCLOSURE A signallight for displaying visual commands, including a housing having anopening therein and a light source disposed within the housing foremitting a beam of light in a forward direction through the opening. Inorder to control the horizontal divergence of the beam of light there isprovided a plurality of elongated, generally at light baflles and meansfor releasably mounting each of the light baies with respect to thehousing and forward of the light source. The bafes are substantiallyvertically oriented and spaced apart in substantially parallel planes,whereby the horizontal divergence of the beam of light is controlled byits passage between the batlles.

This application pertains to the signal light art and more particularlyto an improved light beam director.

The invention is particularly applicable for use with signal lights ofthe type employed in controlling vehicles or pedestrians, such as traicsignals, lane direction control signals, and pedestrian crossingsignals, and will be described with particular reference thereto;however, it is to be appreciated that the invention has broaderapplications and may be used whenever it is desired to control thehorizontal divergence of a beam of light.

Signal lights of the type used for controlling vehicular or pedestriantraffic have, heretofore, usually comprised: a housing adapted to besupported at the side of, or suspended over, a roadway; a cover securedto the front of the housing and having an opening therein which containsa lens; a light source disposed within the housing for generating a beamof light in a forward direction through the lens, and a visor extendingoutward from the cover and surrounding at least a portion of theopening. The above-described traffic signal produces a beam of lightwhich diverges extensively in a horizontal direction as it passesthrough the lens. In typical installations, beam divergence poses noproblem. In fact, it is sometimes a desired characteristic, such aswhere a single suspended overhead traffic signal must be visible todriv- 'ers operating vehicles in multiple adjoining lanes travelling inthe same direction.

Roadway configurations and tratlic control patterns do arise wherein itis desired to limit the horizontal divergence of the beam of light. Onesuch situation exists when roadways intersect at angles much less than90. In this type of intersection it is important to insure that the beamof light is properly aimed down the roadway which it is to control,since a widely diverging beam might confuse approaching driversoperating on the other roadway, thereby creating a potentially dangerouscondition. Another situation in which horizontal beam divergence is ofvital importance arises when certain traffic lanes are intended forspecic uses and individual signals are provided to control such uses.Thus for example, roadways which carry a large volume of vehiculartraffic sometimes include a center lane intended exclusively for leftturns. When this type of roadway design is employed, one overhead signalis used to control the left turn lane 3,543,235 Patented Nov. 24, 1970ICC and another overhead signal is used to control the through lines. Assuch, it is important to limit horizontal beam divergence in order toprevent the driver wishing to make a left turn from being misdirected bythe signal light used to control through lanes, since this would causehim to make a left turn in the face of oncoming trathc. Therefore, it isof vital importance to insure that the driver who is in the left turnlane cannot be confused by the through lane signal, and similarly, thatthe drivers in the through lanes cannot be confused by the left turnsignal. To prevent such confusion, it becomes necessary to restrict thehorizontal divergence of the light beams generated by these respectivesignals.

Various devices have been employed in the past in order to cope with theproblem of tratiic signal light beam divergence. One such device uses anelongated visor having light bailles permanently secured therein whichreplaces the standard visor on the signal housing cover. This type ofbeam director is described in U.S. Pat. No. 2,540,389 to Fowler. Anothermethod of controlling beam divergence involves the use of a special lenspermanently mounted in the visor having a vertical prism configurationthereon to narrow the light pattern. These two devices have provedunsuccessful due to their limited capabilities. More particularly, inthe visor and bale arrangement the light pattern is dependent entirelyon the length of the visor and the spacing of the baies. Since thebat-lies are permanently secured to the visor, each device must bedesigned for a particular application and cannot be used elsewhere norvaried if conditions change. Similarly, the visor and prism lensarrangement also produces a light pattern which is permanently fixed anddependent exclusively on the length of the visor and the opticalcharacteristics of the prism. Another approach which has been triedinvolves the use of a cornplex optical system having a condensing lens,and a series of light bafiies that can be focused and adjusted tosatisfy the requirements of a particular installation. While this deviceovercomes some of the problems heretofore discussed, it results in aproduct which is very sophisticated and quite costly, and therebyputting it beyond the reach of most municipal budgets.

The present invention contemplates a new and improved apparatus Whichovercomes all of the above-referred problems and others by providing anadjustable light beam director which is not only simple and economicalto manufacture, but is also capable of producing a variety of lightpatterns depending upon the particular installation requirements.

In accordance with the present invention there is provided a signallight for displaying visual commands, including a housing having anopening therein and a light source disposed within the housing foremitting a beam of light in a forward direction through the opening; theimprovement for adjustably controlling the horizontal divergence of thebeam of light comprising: a plurality of elongated, generally tlat lightbales; and means for releasably mounting each of the light baflles withrespect to the housing and forward of the light source, the battlesbeing substantially vertically oriented and spaced apart insubstantially parallel planes, whereby the horizontal divergence of thebeam of light is controlled by its passage between the battles.

The principal object of the present invention is to provide an improvedlight beam director for controlling the horizontal divergence of a beamof light.

Another object of the present invention is to provide an improved lightbeam director which can be adjusted in order to meet the specific needsof a particular installation.

A further object of the present invention is to provide an improvedlight beam director that can be used with commercially available signallights.

A still further object of the present invention is to provide animproved light beam director which is simple and economical tomanufacture.

These and other objects and advantages will become apparent from thefollowing description used to illustrate the preferred embodiment of theinvention when read in connection with the accompanying drawings inwhich:

FIG. 1 is a pictorial view of a conventional signal light assemblyshowing the cover in the open position and a light beam directoraccording to the preferred embodiment of the present invention installedtherein;

FIG. 2 is a front elevational view of the light beam director of FIG. 1;

FIG. 3 is a cross-sectional view taken along line 3 3 of FIG. 1;

FIG. 4 is a diagram illustrating the effect of the subject invention ona beam of light;

FIG. 5 is a diagram illustrating the effect of the subject invention ona beam of light; and

FIG. 6 is a diagram illustrating the effect of the subject invention ona beam of light.

Referring now to the drawings wherein the showings are for the purposeof illustrating the preferred embodiment of the present invention onlyand not for the purpose of limiting same, FIG. 1 shows a conventionalsignal light assembly, designated generally by the reference letter A,having a light beam director, designated generally by the referenceletter B, according to the present invention installed therein.

Commercially available signal light assemblies A generally comprise: ahousing 10, manufactured from a corrosion resistant material; a cover 12pivotly connected to the front of the housing for gaining accessthereto; and a light source 14 disposed within the housing. The lightsource 14 is located approximately in the middle of a hinged refiector16 and generates a beam of light in a forward direction through anopening in the cover 12. In a conventional installation, a lens (notillustrated) is mounted in the cover opening. This lens will varydepending upon the application to which the signal light is being put.Examples of such lenses may be found in the Manual of Uniform TrafiicControl Devices, published by the United States Department of Commerce.

Reference is now made to FIGS. 1-3, wherein there is illustrated thelight beam director B of the subject invention which will be describedin detail. In accordance with the present invention there is provided aframe assembly which may take many forms; however, in the preferredembodiment it takes the form of a pair of generally rectangular,parallel frame members 18. Secured to the upper and lower portions ofthe frame members 18 are a pair of vane supports 20, to be described inmore detail later. A lens mounting plate 22 having an annular opening 24therein is disposed rearward of the frame member 18 by securing it tothe vane supports 20 with bolts 26. The aforementioned components,namely the frame members 18, the vane supports 20 and the lens mountingplate 22, are dimensionally capable of being secured to a conventionalsignal housing cover -12, by inserting means into the area defined bythe cover (as shown in FIGS. 1 and 2).

Secured to the rear surface of the lens mounting plate 22 by means ofscrews 32 and lens mounting clips 34 is a first lens 36. Intermediatethe lens mounting plate 22 and the first lens 36 is a lens gasket 38which surrounds the annular opening 24 and the lens mounting plate.Integral with the first lens 36 and arranged on the rear face thereofare a plurality of substantially horizontal prisms 40 which areoptically designed to deflect the beam of light generated by the lightsource 14 in a downward direction as it passes through the first lens.It is to be appreciated that the specific configurations of the prisms40 will vary depending upon the particular optical characteristics whichare desired to be achieved. Thus for example, if the signal lightassembly A is suspended over the roadway, it will be necessary todeflect the beam of light downward so that it can be readily viewed bydrivers in approaching vehicles.

Mounted in the front portion of the frame assembly by means of screws 42and lens mounting clips 44 is a second lens 46 which is substantiallyparallel to the first lens 36 and in spaced-apart relationshiptherewith. The second lens 46, as opposed to the first lens 36, isplain, having no optical structure arranged on either its front or rearsurface. It is to be appreciated that the second lens 46 may take on avariety of appearances. For example, if the signal light assembly A isbeing used in a conventional stop light configuration, then the firstlens 36 would either be red, amber, or green, and the second lens 46would be transparent. If on the other hand, the signal light assembly Awere being used as a lane direction controller, portions of the -secondlens 46 would be coated with an opaque medium while other portions wouldremain uncoated and hence transparent. The transparent portions would beconfigured to define a message or symbol capable of illumination whenthe light source 14 projects a beam of light through the cover 12.Furthermore, the message or symbol can possess color characteristics bymerely employing a colored first lens 36. Examples of typical messagesor symbols may be found in the Manual on Uniform Traffic ControlDevices, published by U.S. Department of Commerce (1961).

Disposed within the frame members 18 and intermediate the rst lens 36and the second lens 46 are a plurality of substantially vertical,parallel vanes 5 2. In accordance with the present invention there isprovided means for releasably mounting the parallel vanes 52 within theframe members 18 which may take many fof ms; however, in the preferredembodiment this takes the form of vane supports 20 having a plurality ofelongated slots 54 disposed therein. The elongated slots 54 are spacedquite close together and in most applications the number of slots willexceed the number of parallel vanes 52 which are installed therein. Thespace between adjoining vanes 52 defines an open area 56 through whichthe beam of light passe-s. Since the number of elongated slots 54exceeds the number of parallel vanes 52, it is possible to adjust thehorizontal distance between vanes to either increase or decrease theopen area 56. By so doing, the horizontal divergence of the beam oflight is either increased or decreased respectively. According to thepresent invention, it is preferred that the horizontal distance xbetween adjoining parallel vanes 52 be the same between each and everyvane, and further that the horizontal distance x approximately comprisesthe range from s inch to 1 inch. Since the horizontal distance x betweenadjoining vanes 52 is capable of adjustment, it can be readily seen thatthe light beam director B may be rapidly and easily tailored to meet theparticular needs of a given installation.

The operational characteristics of the subject invention will now bediscussed by referring to FIGS. 1-6. For purposes of explanation, itwill be assumed that there exists a conventional signal light assembly Awhich generates a beam of light, the horizontal divergence of which isdesired to control, in order to eliminate the possibility of confusingdrivers as to which signal it is that controls the operation of theirvehicle. It will further be assumed that the signal light assembly Aincludes a housing cover 12 of conventional design, and thus capable ofretaining the light beam director B of the subject invention.

In order to install the light beam director B in the housing cover 12the following procedure is carried out. The cover 12 is released fromits normally closed position on the housing 10 by loosening wing-nutcatches 58 and pivoting the cover by means of hinges away from thehousing. The interior of the cover 12 is now readily accessible. A lensgasket 62 is affixed along a lip portion 64 of the cover 12. The secondlens 46 is then inserted in the front portion of the cover 12 and incontact with the lens gasket 62, the latter surrounding the former toassure a tight seal. The frame assembly, including the frame members 18,the vane supports 20, the parallel vanes 52 and the lens mounting 22, isthen inserted in the cover 12 and retained therein by screws 70. It isto be appreciated that the second lens 46 could be directly secured tothe frame assembly by means of lens mounting clips 44, thus eliminatingone of the installatori operations, or in the alternative the secondlens 46 could be inserted separately as heretofore described, andretained in place by the clips 44 exerting a pressure thereon. The lensgasket 38 is installed around the annular opening 24 in the lensmounting plate 22. The first lens 36 may now be secured to the lensmounting plate 22 by means of screws 32 and lens mounting clips 34. Theutmost of care must be exercised when installing the first lens 36 toassure that the prisms 40 are arranged in a horizontal direction andfurther that they face rearward toward the light source 14 when thecover 12 is in the normally closed position. The light beam director Binstallation is now complete and the cover 12 may once again be securedin its normally closed position on the housing by tightening thewing-nut catches 58. A neoprene gasket 72 carried in the rear surface ofthe cover 12 assures a tight seal between the cover and the housing 10to prevent water and dirt from getting into the housing and causingdamage to the various components.

The light beam director B is constructed in a manner which permits theparallel vanes 52 to be horizontally adjusted to either increase ordecrease the distance x between adjoining vanes. This procedure would becarried out prior to installation in the signal light assembly A, and ifat a later date it is determined that adjustments must be made to thebeam director B, this can be rapidly and easily carried. The uniqueadjustment feature of the subject invention was not heretofore availableand as such, constitutes a substantial advance in the art.

Reference will now be made to FIGS. 4-6, wherein there is showndiagrammatically the optical characteristics of the subject invention.The horizontal divergence which a beam of light will achieve,hereinafter referred to as the angle z, is dependent upon two elements:the horizontal distance x between adjoining parallel vanes 52; and, thewidth of the parallel vanes, designated by the dimension y in FIG. 2. Bychanging either dimension x or y it is possible to either increase ordecrease the angle z in order to assemble a light beam director B whichwill meet the speciiic requirements of a particular installation. InFIG. 4 the dimension x equals a 1A inch and the dimension y equals 23Ainches. This configuration will produce an angle z of 4 33 and project alight beam having a width of 8.8 feet at a distance of 50 feet, a widthof 40.5 at a distance of 250 feet and a width of 80.1 feet at 500 feet.

In FIG. 5 the dimension X equals a 1A inch and the dimension y equals21/2 inches. The use of this configuration will result in an angle zequal to 459'. A comparison of FIGS. 4 and 5 reveals that the angle z isinversely proportional to the width of the vanes 52; thus, increasingthe dimension y will decrease the angle z, and conversely, decreasingthe dimension y will increase the angle z.

Referring now to FIG. 6 wherein the dimension x is shown as 1A; inch andthe dimension y is shown as 2% inches. This configuration will yield anangle z equal to 157 and project a light beam having a width of 4.3 feetat a distance of 50 feet, a width of 17.8 feet at a distance of 250feet, and a width of 34.7 feet at a distance of 500 feet. A comparisonof FIGS. 4 and 6 reveals that the angle z is directly proportional tothe dimension x;

thus, by increasing the distance between adjoining parallel vanes 52 theangle z will be increased, and conversely, by reducing the horizontaldistance between adjoining vanes the angle will be decreased.

In view of the foregoing it can be readily seen that the subjectinvention provides an adjustable light beam director which can be usedwith commercially available signal lights to accurately control thedivergence of a beam of light.

Having thus defined our invention, we claim:

1. In a signal light for displaying visual commands, including a housinghaving an opening therein and a light source disposed within the housingfor emitting a beam of light in a forward direction through the opening;the improvement for adjustably controlling the horizontal divergence ofthe beam of light comprising: a plurality of elongated, generally flatlight bafiies; and means for releasably mounting each of said lightbaiiies with respect to said housing and forward of said light source,said baffles being substantially vertically oriented and spaced apart insubstantially parallel planes, whereby the horizontal divergence of saidbeam of light is controlled by its passage between said baiiies.

2. A light beam director for use with signal lights, comprising: a lightsource for emitting a beam of light in a forward direction; meansmounted forward of said light source for directing said beam of light ina generally downward direction; a plurality of elongated, generally fiatlight baliies; means for releasably mounting each of said baies forwardof said light source and Xed with respect to said directing means; saidbaffles being substantially vertically oriented in said mounting meansand spaced from each other in substantially parallel planes, whereby thehorizontal divregence of said beam of light is controlled by its passagebetween said baffles.

3. The light beam director of claim 2, wherein said directing meanscomprises a lens having a plurality of horizontally arranged prismsdisposed on one of its faces.

4. The light beam director of claim 3, wherein said lens is locatedintermediate said light source and said baffles.

5. The light beam director of claim 2, further including secondary lensmeans for confining said beam of light to define a preselected image.

6. In a signal light of the type used for controlling Vehicular orpedestrian traliic, including a housing, a cover secured to the front ofthe housing and having an opening therein, and a light source disposedwithin the housing for emitting a beam of light in a forward directionthrough the cover opening; the improvement comprising: a frame assemblyhaving front and rear portions and horizontal and vertical axes; saidframe assembly secured to said cover with said rear portion adjacentsaid housing, whereby said beam of light passes through a chamberdefined by said frame assembly; a first lens having front and rear facesmounted in said rear portion of said frame assembly; prism meansarranged on one face of said first lens for deecting said beam of lightin a downward direction; said prism means being substantially parallelto the horizontal axis of said frame assem- |`bly; and a plurality ofsubstantially vertical, parallel vanes releasably retained in said frameassembly, the space between adjoining vanes defining an open areathrough which said beam of light passes.

7. The light beam director of claim 6, wherein said prism means isarranged on the rear face of said first lens.

8. The light beam director of claim 6, further including a second lensmounted in the front portion of said frame assembly, portions of ,saidsecond lens being coated with an opaque medium, said uncoated portionsbeing transparent and coniigured to define a message or symbol, wherebythe message or symbol is adapted to be illuminated when the beam oflight passes through said lens.

9. The light beam director of claim 6, wherein said parallel vanes areequally spaced apart from each other in the horizontal direction.

10. The light beam director of claim 9, further including means foradjusting the horizontal dimension between adjoining parallel vanes.

11. A light beam director for use with signal lights of the type havinga housing, a cover secured to the housing and including an openingtherein, and a light source disposed within the housing for generating abeam of light in a forward direction through the cover opening, saidlight beam director comprising: a frame assembly having front and rearportions, and horizontal and vertical axes; said frame assembly adaptedto be mounted in the signal light cover with said rear portion adjacentthe signal light housing, whereby the beam of light passes through achamber defined by said frame assembly; a rst lens mounted in said rearportion of said frame assembly;

prism means arranged on one face of said first lens for deecting thebeam of light in a downward direction; said prism means beingsubstantially parallel to the horizontal axis of said frame assembly;and a plurality of substantially vertical, parallel vanes releasablyretained in said frame assembly, the space between adjoining vanesdening an open area through which the beam of light passes.

References Cited UNITED STATES PATENTS 2,312,074 2/1943 Campbell 340-114HAROLD I. PlTTS, Primary Examiner U.S. Cl. X.R.

